Benitoite Gemstone & Information | Gemopedia by JTV | Gemopedia™
Benitoite is a single-source gemstone, meaning that so far, it has been found in only one place on Earth: San Benito County, California. Benitoite grows in relatively small crystals, only a portion of which are gem quality--further increasing the rarity and value of this unique gemstone. Gem-quality benitoite over one carat is incredibly difficult to come by. California's state gemstone, benitoite is especially prized by collectors for its strong dispersion, which rivals that of diamond in lighter material.
Blue, Violetish Blue, Colorless, Zoned With Light Blue, White, Very Rarely Pink
Benitoite classificationCommonNameBenitoiteSpeciesBenitoiteVarietyColorsBlue, Violetish Blue, Colorless, Zoned With Light Blue, White, Very Rarely PinkAlternateNamesGemstoneGroupsKeySeparationsrefractive index, birefringence, optic character, pleochroism and possibly fluorescenceClassificationComments
Benitoite chemistry & crystallographyChemicalNamebarium titanium silicateChemicalFormulaBaTiSi3O9SynthesisCrystalSystemHexagonalChemistryClassificationSilicateNatureNaturalCrystallinityCrystallineChemistryComments
Benitoite optical propertiesTransparencyTransparentDispersionStrength: moderate fire Value: 0.044OpticalCommentsRefractiveIndexOver the Limit 1.757-1.804Birefringence0.047-0.047OpticCharacterUniaxialOpticSignPositivePolariscopeReactionDoubly Refractive (DR)FluorescenceSWUV: Inert to strong bluish white
LWUV: Inert to weak redCCFReactionPleochroismDichroic, strong blue and colorless
Benitoite characteristic physical propertiesHardness6-6.5CharacteristicCommentsStreakWhiteSpecificGravity3.61-3.69 Range:0.01/-0.07 Typical:3.68ToughnessFairInclusionsBenitoite may be color zoned with strong pleochroism.LusterVitreousStabilityFractureConchoidal, UnevenCleavagePoor, in one direction